package LinkedList;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 86138
 * Date: 2024-07-25
 * Time: 17:31
 */
public class MyLinkList implements IList{
    static class ListNode{
        public int val;
        public ListNode next;

        public ListNode(int val){
            this.val = val;
        }
    }

    private ListNode head;



    //头插法
    public void addFirst(int data){
        ListNode node = new ListNode(data);
        node.next = head;
        head = node;
    }
    //尾插法
    public void addLast(int data){
        ListNode node = new ListNode(data);
        if(head == null){
            head =  node;
        }
        ListNode cur = head;
        while (cur.next!=null){
            cur = cur.next;
        }
        cur.next = node;
    }
    //查找是否包含关键字key是否在单链表当中
    public boolean contains(int key){
        ListNode cur = head;
        while (cur!=null){
            if(cur.val == key){
                return true;
            }
            cur = cur.next;
        }
        return false;
    }
    //任意位置插入,第一个数据节点为0号下标
    public void addIndex(int index,int data){
        int len = size();
        if(index == 0){
            addFirst(data);
        }
        if(index == len){
            addLast(data);
        }
        ListNode cur = head;
        while(index-1!=0){
            cur = cur.next;
            index--;
        }
        ListNode node = new ListNode(data);
        node.next = cur.next;
        cur.next = node;
    }
    //删除第一次出现关键字为key的节点
    public void remove(int key){
        if (head ==null){
            return;
        }
        if(head.val == key){
            head = head.next;
            return;
        }

        ListNode cur = findNodeOfKey(key);
        if(cur == null){
            System.out.println("没找到");
            return;
        }
        ListNode del = cur.next;
        cur.next = del.next;

    }

    public ListNode findNodeOfKey(int key){
        ListNode cur = head;
        while (cur.next != null){
            if(cur.next.val==key){
                return cur;
            }
            cur = cur.next;
        }
        return null;
    }
    //删除所有值为key的节点
    public void removeAllKey(int key){
        if(head == null){
            return;
        }
        ListNode cur = head.next;
        ListNode pre = head;
        while (cur != null){
            if(cur.val == key){
                pre.next = cur.next;
                cur = cur.next;
            }else{
                pre = pre.next;
                cur = cur.next;
            }
        }
            if (head.val == key){
                head = head.next;
            }
    }
    //得到单链表的长度
    public int size(){
        ListNode cur = head;
        int count = 0;
        while (cur!=null){
            count++;
            cur = cur.next;
        }
        return count;
    }
    public void clear(){


    }
    public void display(){
        ListNode cur = head;
        while (cur!=null){
            System.out.print(cur.val + " ");
            cur = cur.next;
        }
    }
}
